Rejection type fuse holder

ABSTRACT

The fuse clip includes opposed arms, at least one of which is deflectable, for receiving the end terminal of a fuse cartridge. Maximum separation between the arms is determined by an abutment operatively associated with the deflectable arm. An obstruction is formed on at least one of the arms which is accommodated in an appropriately grooved fuse end terminal to accept insertion thereof. The obstruction engages an ungrooved fuse end terminal to thus require a separation of the arms precluded by the abutment, thereby rejecting insertion.

United States Patent 1191 Tillson Oct. 21, 1975 [54] REJECTION TYPE FUSEHOLDER FOREIGN PATENTS OR APPLICATIONS Inventor: Robe" Tent/ville Conn-535,610 4/1941 United Kingdom 339/258 F [73] Assignee: General ElectricCompany, New

York, NY. Primary Examiner-Joseph H. McGlynn Attorney, Agent, or FirmR.A. Cahill; W. C. [22] Flled' 1974 Bernkopf; F. L. Neuhauser [21] Appl.No.: 532,009

Related US. Application Data [57] ABSTRACT Division Of Sl'. NO. Jan. 16,Pat. NO. The fuse includes opposed arms at least one of 3,890,031 whichis deflectable, for receiving the end terminal of a fuse cartridge.Maximum separation between the [52] US. Cl; 339/186 R; 339/258 F arms idetermined by an abutment operatively i [51] Int. Cl. HOIR 13/64 atedwith the deflectable An obstruction i [58] Field of Search 339/147, 184,186, 252, formed on at least one of the arms which is accommw 339/253262 dated in an appropriately grooved fuse end terminal to acceptinsertion thereof. The obstruction engages an [56] References C'tedungrooved fuse end terminal to thus require a separa- UNI ED STA ESPATENTS tion of the arms precluded by the abutment, thereby 1,218,2213/1917 Smith 339/258 F j ting insertion. 2,942,228 6/1960 Swick.....2,943,295 6/1960 Stewart 339/258 F 4 Clams 7 Drawmg US. Patent Oct. 21,1975 3,914,005

REJECTION TYPE FUSE HOLDER I This is a division of application Ser. No.433,824,

filed Jan. I6, 1974, now US. Pat. No. 3,890,032.

BACKGROUND OF THE INVENTION This invention relates generally to a fuseclip structure for accepting an appropriately keyed fuse end terminaland rejecting an improperly keyed fuse end terminal. More specifically,the present invention relates to a fuse clip for only accepting aferruled fuse end ter minal which is appropriately grooved.

Rejection-type fuse clips for ferruled end terminals are known asevidenced by US. Pat. No. 2,943,295. In this patent, a separateinterference means is assembled with a fuse clip, the latter including apair of deflectable clamping arms formed for receiving a ferruled endterminal. The rejection means includes a rigid U-shaped member extendingupwardly into the space between the clamping arms. The clamping armsdeflect independently of the rejection means through appropriate slotsin their side walls. The clearance across the U-shaped membercorresponds to the outside diameter of a corresponding annular recess ina ferrule of an end terminal specifically formed for reception by thefuse clip. When such a ferrule is inserted, the clamping arms deflectoutwardly independently of the rejection means to receive thenon-recessed surface of the end terminal. The rejection means acts toprevent proper seating of an ungrooved ferrule.

Another type of rejection fuse clip for a ferrule type end terminal,disclosed in U.S. Pat. No. 2,558,581, includes a projection orprotuberance on one side wall of an essentially rigid semicylindricalseat. When a ferruled end terminal not including a special recess foraccommodating the aforesaid projection is presented for insertion intothe clip, the projection in effect reduces the inside diameter of theseat to less than the ferrule diameter, thus to prevent proper seatingtherein which is determined and maintained by a separate screw clamp.

.The disadvantage of the first form of fuse clip structure resides inthe fact that an unknowledgeable or non-observant installer couldpartially insert an. improper fuse such that, although not fully seated,it is nevertheless physically held and electrically inserted into thecircuit to be protected. In the latter form, the

.fuse holder, though possibly more foolproof, is rela- Other objects ofthe present invention will be apparent to those skilled in the art.

SUMMARY OF THE INVENTION Briefly stated, the present invention providesa fuse clip for reception of an appropriately formed end terminal of afuse cartridge. The fuse clip, at at least one' end of the fuse holder,includes a pair of spaced arms,

at least one of which being deflectable. At least one of the armsincludes an arcuate mid-section for correspondingly receiving an arcuateportion of a ferruled fuse end terminal inserted in the pockettherebetween. One of the arms carries an interference means orobstruction which, extends laterally into the pocket adjacent the accessopening thereto. In addition, a deflection limiting means or abutment ispositioned externally of the pocket in closely spaced relation to thedeflectable arm to limit the lateral dimension of the pocket openinginduced by the forcible insertion of a ferruled end terminal. Thismaximum lateral dimension or clearance between the arms is adequate toadmit the insertion of a ferruled end terminal keyed with a recess orgroove located to accommodate the obstruction, but insufficient so as todeny insertion of an ungrooved end terminal since the obstruction bearsagainst the outer surface of the end terminal to increase the clearancerequisite to insertion; such clearance increase being prohibited by theabutment.

DESCRIPTION OF THE DRAWINGS The subject matter which is regarded as theinvention is particularly pointed out and distinctly claimed in theconcluding portion of the specification. The invention, however, both asto organization and method of practice, together with further objectsand advantages thereof, may be best understood by reference to thefollowing description taken in conjunction with the accompanyingdrawings in which:

FIG. 1 is a side view of one fuse clip embodiment of the presentinvention.

FIG. 2 is a top view of the fuse clip shown in FIG. 1.

FIG. 3 is a side view of an alternative fuse clip embodiment of theinvention.

Hg. 4 is a side view of another fuse clip embodiment of the presentinvention.

FIG. 5 shows still another fuse clip embodiment of the presentinvention.

FIG. 6 is a side view of the fuse clip embodiment of FIG. 1 illustratingacceptance of a properly keyed, ferruled fuse end terminal.

FIG. 7 is a side view of the fuse clip embodiment of FIG. 1 illustratingrejection of an improperly keyed, ferruled fuse end terminal.

Like reference numerals refer to corresponding parts throughout theseveral views of the drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1 of thedrawings, which shows one embodiment of the invention, a fuse clip 10 isgenerally shown, the main body of which includes a base member 12 andtwo spaced apart clamping arms 14 and 16 which extend upwardly from thebase member 12 in a cantilevered manner. Base member 12 is secured to asupport 13 by a rivet or screw 15. The clamping arms 14 and 16 areseparated from one another in their normal disposition to define apocket 18 and are substantially parallel to one another. The clampingarm 16 includes an arcuate mid-portion for engaging a correspondingarcuate side of a ferruled end terminal of a cartridge fuse. Aninterference means or obstruction 20 is disposed on clamping arm 14 andextends laterally into pocket. 18 to reduce the transverse clearance ofthe entrance or opening to the pocket defined by the upper end portionsof the two clamping arms.

vAn L-shaped deflection limiting means, as seen in FIG. 2 of thedrawings, has a leg portion 22 affixed to and extending from the sideedge of clamping arm 14 transversely beyond the end of pocket 18 towardflexible clamping arm 16. Leg portion 22 terminates in a turned footportion 24 located on the opposite side of a'rm,l6 from pocket 18 toserve as a substantially rigid abutment limiting the maximum deflectionof arm 16 and thus the maximum lateral dimension of the opening into thepocket.

In the alternative embodiment of the present invention shown in FIG. 3,an additional interference means or obstruction in the form of a post 26is riveted or otherwise secured to the free end portion of arm 16 intransverse alignment with obstruction 20. Post 26 is provided to preventdeformation of the uppermost crooked portion of clamping arm 16 againstabutment 24 upon attempted insertion of an end terminal of a cartridgefuse not keyed for reception in the fuse clip. Post 26 cooperates withobstruction 20 reject insertion of an unkeyed, ferruled end terminal,while the former effectively resists insertion forces tending to flattenout the uppermost crooked portion of the clamping arm 16 againstabutment 24, and thus over-ride the rejection feature of the invention.In addition, it is to be noted that the deflection limiting means can beseparately affixed to the clamping arm 14 as shown in FIG. 3 as opposedto the integral nature of the attachment to the clamping arm shown inFIG. 2. It will also be noted that this attachment, in the form of arivet, etc., can also mount or constitute in whole or in part theobstruction 20.

A further alternative embodiment of the invention is shown in FIG. 4 toinclude a clip body having arms and an interconnecting base in a similarconfiguration to that illustrated for the embodiments of FIGS. 1 and 3.

However, mounting of the clip body and the deflection limiting means isprovided by a mounting block 28. Specifically, the mounting block isformed having a U- shaped cavity with the clip body supported by thecavity floor 28a while arm 14 is situated against one cavitysidewall'28b. The other deflectable arm 16 is upstanding in closelyspaced relation to the other cavity sidewall, which constitutes thedeflection limiting abutment 24. In this embodiment, arm 14 is slottedto accommodate obstruction 20 which is formed on or attached to cavitysidewall 28b.

The embodiment of the invention shown in FIG. 5 of the drawings issimilar to that shown in FIG. 4 except that the deflection limitingmeans is constituted by both sidewalls of the cavity formed in mountingblock 28. Consequently, the arms 14 and 16 are identically,complementarily shaped and are both deflectable; theirdeflectionmovements being limited in magnitude by the closely spacedcavity sidewalls. In addition, the interference means is in the form ofa pair of opposed obstructions extending inwardly at the opening intocavity 18 from the clamping arms.

The mode of operation and principal advantage of the present inventioncan be understood from a comparison of FIGS. 6 and 7 of the drawings. InFIG. 6, a ferruled end terminal 34 is received in the fuse clip 10. Anannulargroove 36 in the end terminal 34 receives the interference means20 and the outside or major diameter of the non-recessed portion of theend terminal is dimensioned to correspond to the maximum clearancebetween the arms at the opening into the pocket as established by thedeflection limiting means. In FIG. 7, a ferruled end terminal 34a notgrooved to accept the interference means requires an opening clearanceinto the pocket in excess of the maximum allowed clearance. It is seenthat the interference means bears against the outer surface of the endterminal, thus, in effect, adding its length to the major diameter ofthe end terminal to create a total clearance requirement exceeding thatpermitted by the limiting means 24. Entry into the pocket 18 istherefore denied. It will be noted that the location of the interferencemeans adjacent the entrance or opening into the pocket affords rathercomplete rejection in that even partial insertion of an ungrooved endterminal is precluded. Thus the fuse clip of the present inventioneffectively precludes any retention whatsoever of an improperly ratedfuse.

While a number of embodiments of the present invention have beenspecifically disclosed herein, other modifications will occur to thoseskilled in the art and it is desired to cover in the appended claims allsuch modifications as fall within the true spirit and scope of theinvention.

We claim:

1. A fuse clip for accommodating a fuse end terminal appropriately keyedwith a special recess, said fuse clip comprising, in combination:

A. a pair of spaced arms defining therebetween a C. limiting meansdisposed externally of said pocket adjacent said deflectable arm forlimiting the deflection thereof so as to establish a maximum separationof said arms at said pocket opening corresponding to the major lateraldimension of a fuse end terminal having the keyed recess foraccommodating said interference means upon insertion, said interferencemeans engaging the outer surface of a fuse end terminal lacking thekeyed recess to increase the separation of said arms at said pocketopening necessary for insertion to a spacing which is prohibited by saidlimiting means, thereby to re. ject insertion thereof; and

D. a mounting block for supporting said arms, said limiting means beingprovided by a surface of said block.

2. The fuse clip defined in claim 1, wherein said arms are situated in acavity formed in said block, said limiting means being provided by asidewall of said cavity.

3. The fuse clip defined in claim 2, wherein said interference means iscarried by said other cavity wall for extension into said pocket.

4. The fuse clip defined in claim 2, wherein both of said arms aredeflectable, said interference means is carried by at least one of saidarms and said limiting means is provided by opposed sidewalls of saidcavity disposed in deflection limiting physical relation with said arms.

1. A fuse clip for accommodating a fuse end terminal appropriately keyedwith a special recess, said fuse clip comprising, in combination: A. apair of spaced arms defining therebetween a pocket having a constrictedopening for receiving a fuse end terminal, at least one of said armsbeing deflectable to accommodate enlargement of said pocket opening; B.interference means approximate one of said arms and extending laterallyinto said pocket adjacent said opening; C. limiting means disposedexternally of said pocket adjacent said deflectable arm for limiting thedeflection thereof so as to establish a maximum separation of said armsat said pocket opening corresponding to the major lateral dimension of afuse end terminal having the keyed recess for accommodating saidinterference means upon insertion, said interference means engaging theouter surface of a fuse end terminal lacking the keyed recess toincrease the separation of said arms at said pocket opening necessaryfor insertion to a spacing which is prohibited by said limiting means,thereby to reject insertion thereof; and D. a mounting block forsupporting said arms, said limiting means being provided by a surface ofsaid block.
 2. The fuse clip defined in claim 1, wherein said arms aresituated in a cavity formed in said block, said limiting means beingprovided by a sidewall of said cavity.
 3. The fuse clip defined in claim2, wherein said interference means is carried by said other cavity wallfor extension into said pocket.
 4. The fuse clip defined in claim 2,wherein both of said arms are deflectable, said interference means iscarried by at least one of said arms and said limiting means is providedby opposed sidewalls of said cavity disposed in deflection limitingphysical relation with said arms.